1. Field of the Invention
The present invention relates to a reverse idler system for use with an automotive transmission, and more particularly, to a two-piece continuous mesh synchronized reverse idler system.
2. Description of Related Art
Automotive manual transmissions are typically designed with an input shaft supporting a plurality of drive gears having varying diameters, as well as an output or an intermediate shaft supporting a plurality of driven gears having varying diameters and meshingly engaged with the drive gears of the input shaft. By selectively engaging the driven gears with the output or intermediate shaft, varying transmission gear ratios are obtained.
Typical manual transmission reverse systems use an axially sliding spur gear idler configuration. Power is transmitted from a reverse gear on the manual transmission input shaft to the reverse gear on the intermediate shaft by a reverse idler used to reverse rotational direction of the intermediate shaft. The reverse gear on the intermediate or the output shaft is fixedly engaged with the intermediate shaft. To engage reverse, the reverse idler gear is moved axially along the reverse idler shaft by a lever arrangement, and is slid into mesh with both the input shaft reverse gear and the reverse gear on the intermediate shaft. All three gear elements are spur gear designs. Pointing features are arranged on the ends of the spur gear teeth to index the gears so the idler gear can slide entirely into position. Because of the constraints associated with a sliding idler gear design, imprecise engagement exists which result in clash and block outs. Furthermore, packaging restrictions can limit the amount of tooth engagement available, which results in durability related problems of the spur gear design. Gear noise can also be objectionable with spur gears.